Brake system with redundancy

Abstract

The present invention concerns a brake system creating redundancy in electromechanical brakes. At least two drive units are provided at each single brake for activation of the brake. The at least two units may be controlled and/or energized separately. To safeguard the function the control and/or energy source systems are formed in two nets. The at least two units of each brake are connected to separate nets. The at least two units may be separate electrical motors.

1 . A brake system characterized in that each single brake has a redundancy regarding activation and that at least two drive units are provided at each single brake for activation of the brake.  
   
   
       2 . The brake system of  claim 1 , characterized in that the at least two units at each brake are energized and/or controlled separately.  
   
   
       3 . The brake system of  claim 2 , characterized in that the energy source and/or control systems are formed in two nets, whereby the units of each brake are connected to separate nets.  
   
   
       4 . The brake system of  claim 1 , characterized in that the at least two units are two separate electrical motors with two separate shafts and a rotational speed reduction.  
   
   
       5 . The brake system of  claim 4 , characterized in that the motors of each brake are working in opposite directions.  
   
   
       6 . The brake system of  claim 1 , characterized in that the at least two units are two separate electrical motors with two separate shafts and a partly common mechanical transmission.  
   
   
       7 . The brake system of  claim 1 , characterized in that the at least two units are one motor package with thermally and electrically insulated winding packets in an stator portion and a common rotor on a common shaft.  
   
   
       8 . The brake system of  claim 4 , characterized in that each motor winding has its own driver supplied by separate voltage sources.  
   
   
       9 . The brake system of  claim 8 , characterized in that the motor control is performed by two separately supplied control units, each communicating with other parts of the brake system with separate interfaces to separate networks for brake system communication.  
   
   
       10 . The brake system of  claim 8 , characterized in that the motor control is performed by a generally redundant, voltage supplied control unit communicating with the rest of the brake system by two separate interfaces to two separate networks with two smaller, separately voltage supplied emergency control units connected to each drive unit.  
   
   
       11 . The brake system of  claim 1 , characterized in that each brake is a self-energizing brake having a ramp plate provided with a brake pad for braking engagement with a brake disc, the ramp plate being movably connected to two ramp bridges, and that at their surfaces facing each other, the ramp plate and the ramp bridges are provided with ramps and two rollers freely rotatable between the ramps.  
   
   
       12 . The brake system of  claim 11 , characterized in that an angle of the ramps in relation to the brake disc may be altered.  
   
   
       13 . The brake system of  claim 11 , characterized in that the inclination of the ramp bridges and/or the ramp plate in relation to the brake disc is variable.  
   
   
       14 . The brake system of  claim 13 , characterized in that the ramp plate and the ramp bridges are inclined synchronously keeping the angles of the ramps constant in relation to the rollers.  
   
   
       15 . The brake system of  claim 11 , characterized in that two screws are provided at each ramp bridge, one at each end of the ramp bridge, to control the position of each ramp bridge.  
   
   
       16 . The brake system of  claim 15 , characterized in that the screws are controlled separately.  
   
   
       17 . The brake system of  claim 15 , characterized in that the screws are controlled in pairs to alter the angle of the ramps and thereby the self-locking angle of the ramps.  
   
   
       18 . The brake system of  claim 12 , characterized in that the screws are ball screws.  
   
   
       19 . A brake system for a motor vehicle, said brake system comprising: 
 a plurality of brakes, each having a brake actuator;    wherein the brake actuator of at least one of said plurality of brakes comprises: 
 a plurality of separately operable brake application units;  
 wherein said plurality of separately operable brake application units employ electrical energy for brake actuation.  
   
   
   
       20 . The brake system of  claim 19  wherein said plurality of separately operable brake application units comprises a plurality of separate motors with a plurality of separate shafts.  
   
   
       21 . The brake system of  claim 19  wherein said plurality of separately operable brake application units comprises a plurality of thermally and electrically insulated winding packets disposed in a stator portion of a single motor package having a common rotor on a common shaft.